The long-term goal of this project is to develop miniaturized electrospray (or nanospray) emitters that have enhanced durability versus those which are currently available. While nanospray mass spectrometry has improved detection limits, requires less sample volume, and much lower flow rates (resulting in much reduced consumption of analyte), current emitters using gold coatings are highly suspectible to destruction by electrical discharge. Here, we pursue conductive polymer coatings which exhibit high resistance to electrical discharge as alternative coatings for nanospray mass spectrometry. The development of such durable emitters will permit the stable coupling of capillary separations techniques directly to nanospray mass spectrometry for high sensitive detection and characterization of biological molecules directly from complex mixtures of biomolecules in biological fluids (e.g., cerebrospinal fluid, blood plasma, tear fluid, etc.). Such a powerful combination of analytical technologies will have important implications in detecting biomolecules which are indicative of disease states (for example protein isoforms of hemoglobin or prealbumin) as well as providing information on in vivo drug pharmacokinetics by measuring pharmaceutical products to extremely low levels directly from biological fluids (e.g. metabolism of anti-cancer drugs and their metabolic products directly from blood plasma). PROPOSED COMMERCIAL APPLICATION: The development of conductive polymer coated nanospray emitters will provide for the first time a durable nanospray emitter capable of functioning throughout the course of a capillary separations technique coupled directly to nanospray. Thus, analysis of subpicomole levels of biological molecules directly from biological fluids will be possible, with application to biomedicine and pharmaceutical science.